1. Technical Field
The present invention relates to a method of manufacturing a transparent conductive polymer thin film having high conductivity via surface treatment, and to a transparent electrode manufactured using the same.
2. Description of the Related Art
Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) may be mainly provided in the form of an aqueous dispersion to form a polymer thin film, and the conductivity of PEDOT:PSS is as low as 0.1˜1 S/cm. Hence, the conductivity of PEDOT:PSS may be increased by adding the PEDOT:PSS solution with a dimethyl sulfoxide (DMSO) or dimethylformamide (DMF) solution or with a polyhydric alcohol such as ethyleneglycol as a secondary dopant.
However, the addition of such a material may deteriorate stability upon long-term storage of the PEDOT:PSS aqueous dispersion. Also, when glass or a film is coated therewith, surface tension of the solution may increase, and thus wettability on the substrate may become poor, making it difficult to form a uniform film.
With the goal of solving such problems, attempts have been made to subject a polymer thin film formed of the PEDOT:PSS aqueous dispersion to surface treatment so as to increase conductivity.
Specifically, the PEDOT:PSS film is surface-treated using sulfuric acid, hexafluoroacetone, methanol or DMF. Particularly, the use of sulfuric acid may result in great improvements in conductivity. However, sulfuric acid causes severe loss of the PEDOT:PSS film. Furthermore, safety problems of workers may occur due to the use of the strong acid.